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Computer Graphics

Computer graphics have had to develop in line with the processing speed, pixel density and memory capability of computers.

Fine detail on a character depends on how many dots per inch (dpi) there are on the screen monitors, the screen resolution tells you the number of dots (pixels) on the entire screen. For example, a 640-by-480 pixel screen is capable of displaying 640 distinct dots on each of 480 lines, or about 300,000 pixels. This translates into different dpi measurements depending on the size of the screen. For example, a 15-inch VGA monitor (640x480) displays about 50 dots per inch.

When computers had small memory and slow processing speeds it took a relatively long time for a large image of a character to transfer to the screen. If you then wished to make it appear to move, you required the computer to redraw that character in a different position quickly enough for it to fool the human eye. This was impossible on early machines and so the graphics were drawn in a simplistic way.

Nowadays we expect computer graphics to look 'realistic'. That means use of a large palette of colours and computer programs that produce images that are rendered to a high degree of reality, giving the image a 3D quality due to the shading and texture mapping used.